In many situations it is desirable for a user to control equipment or appliances remotely from a control unit which may be hardwired or wireless. This already exists with infrared (IR) controls for TV/video, HiFi and the like. In a domestic environment it is also desirable to control the operation of other items, such as lights, curtains, doors and heaters. Various systems have been proposed such as X10 (X10 Powerhouse, U.S.A.)
Such systems generally have codes which require that each device has an unique code and the control unit has a list of addresses for each device. When multiple controllers are located in the same domain or environment, each controller has to have a copy of the device address list. This means that the list has to be copied and updated in each controller and there is no clear hierarchy of addresses to allow straightforward overall control of groups of devices in a domain.
In addition, people with physical disabilities often have great difficulty coping within a domestic environment. Actions able-bodied people take for granted, such as turning on or off a light or answering the telephone, are impossible for a great many physically disabled people. Such people often rely on a fulltime carer, such as a nurse or a member of the family to undertake these tasks. Hiring a carer is costly and, unfortunately, tends to result in the disable person having little say in how their house is run as the carer or relative tends to adopt set routines and controls the environment as they think best. This is particularly evident when the disabled person has limited verbal skills.
However, many physically disabled people are capable of managing with only limited assistance from a carer, such as at bathtimes and mealtimes, if they are provided with a suitable control system which allows them to operate standard domestic appliances. Such control systems do exist but are based on interfaces developed to allow severely disabled individuals to operate personal computers. These interfaces limit the input requirements of the device so that, instead of a user implementing a sequence of keystrokes requiring manual dexterity, all functions are accessible by only one to two switches. These switches are generally in the form of a joystick which can be pushed into position or a mouthpiece switch into which the user may suck or blow to perform switch selection.
An example of such a control system is disclosed in U.S. Pat. No. 4,979,094 to Possum Controls Limited. A central microprocessor-based control unit is positioned within the home. Independent input stations are located in each room for allowing access by the disabled user. Each input station is connected to the control unit either by direct wiring or using serial wiring linking the stations, and each input station is operable by the disabled user in the manner described above in which the user performs a selection from a coloured scanning menu display appearing on a TV-type screen. The controlled domestic appliances each have a switching unit fitted either within the appliance or via a specially adapted mains plug. The domestic appliances are all connected to the control unit, but may be wired in series to reduce the amount of overall wiring required. The control unit manages the switching traffic and can operate its own stored routines. In addition, an able-bodied user can switch or adjust an appliance within the home and the control unit will detect this and display modified status information to the disabled under when they next view the screen at any input station.
Control systems such as the one described above have a number of disadvantages: they require extensive wiring on installation which makes them difficult to retrofit into a new home; the presence of an input station in each room and the size of a TV screen is both costly and intrusive for other members of the family or guests; a new domestic appliance requires both wiring to the control unit and reprogramming of the microprocessor within the control unit such that the appliance can be identified and controlled from each input station; only one function on one appliance may be switched or adjusted at a time, particularly if the system is wired in series; any appliances which develops a fault has no means with which to send a message to the control unit that such a fault has occurred; in the event of mains power failure, the disabled user loses all control as emergency battery back-up is normally only found on essential medical equipment over which, for safety reasons, the disabled user has no day-to-day control and, if the control unit itself develops a fault, this can cause the entire system to become inoperable.
Because of the possibility of faults developing, most Health Authorities do not wholly rely on such control systems and, instead, use fulltime care assistance. In addition, these systems cannot determine if the disabled user is in difficulty unless they are capable of operating an alarm or telephone. Even in large residential homes for the disabled, such control system are not used due to the need for individuals to monitor faults occurring, for individuals to check on the well-being of the disabled person and the costs of installing a control system.
It is an object of at least one embodiment of the present invention to provide a communication and control system which obviates or mitigates at least one of the aforementioned disadvantages of existing control systems.